Auto ViewModelLocator In MVVM Pattern

Auto ViewModelLocator

I will present a little trick inside of the ViewModels instantiation in MVVM pattern.

Sometimes, we work in WPF small solutions, which does not usually need ViewModelLocator class as ViewModels class generator, because we don’t need to save ViewModels reference. We will not worry about feeding ViewModelLocator class and we will go to deploy our ViewModels classes immediately. This fits perfectly with the unit tests and binding engine.

We will get all this with a class with two WPF attached properties given below.

We will have two cases, which are given below.

• The View name and ViewModel name will have equivalent names.
  
  
  
  
• SameNameClass[View].xaml
• SameNameClass[ViewModel].cs

• View name and ViewModel name don’t have equivalent names.
  
  
  
  
• DifenteNameView.xaml
• DiferentNameViewModel.cs

Equivalents Names (View and ViewModel)

In this case, proceed, as shown below.

In this example, the view Example1View instances an Example1ViewModel object as DataContext automatically.

Not Equivalents Names (View and ViewModel)

In this case, we need to specify another property with the name of ViewModel class.

Note

The property ViewModelClassName has to be in first place.

In this example, the view Example2Window instances an Example2ViewModel object as DataContext automatically.

MLMVVM class

It is a very simple class. It has two AttachProperties and two private methods.

The attachproperties are the previously configured properties.